Effect of air-drying temperature on drying kinetics of four mushroom species in Vietnam

Abstract

     In this study, four mushroom species including pearl oyster mushroom (Pleurotus ostreatus var. florida), blue oyster mushroom (Pleurotus ostreatus var. columbinus), straw mushroom (Volvariella volvacea) and stalks of shiitake mushroom (Lentinula edodes) were dehydrated in convective air dryer at drying air temperatures of 50, 60 and 70oC. During the process, moisture contents were investigated to examine the effect of drying temperature on the rate of moisture loss, to estimate effective diffusion coefficients and activation energy for each material. The results showed that the higher drying temperature the faster the moisture was removed from the materials. Diffusion coefficients and activation energy for each mushroom were in the range of 1.69544x10-10 to 7.82706 x10-10 m2/s and 15.45 to 24.79 kJ/mol, respectively. Moreover, the activation energy for shiitake stalks was relatively higher compared to those of the other mushrooms which indicated that removal of water in shiitake stalks requires more harsh conditions i.e. higher temperature and higher drying time